An enclosure made of two interlocking half sections of o.032" double sided copper PCB material houses a sensitive microsecond integrating circuit operating just above the resistor background Johnson noise level.
This instructable is about making a shielded copper box.ELECTRONIC Brief
A photon from a rare photo multiplier tube feeds a narrow pimple pulse into the single input gold BNC connector.
Inside the double electrostatic shield resides a +- regulated supply see the last two pictures
and the delicate electronics high speed video amplifier / integrator construction in progress.
The noise generating LEDs come on long after electronic photon integration is complete and differing output signals were sent to the silver BNC connectors. LEDs are to indicate signal processing success of critical stages which may or may not happen.CONSTRUCTING a Copper Metal Shield BoxSubstrate :
The PCB material was easily sliced with a big paper cutter into the shapes for the outside six sides. Then place together four sides and tab solder inside edges for a preliminary fit. Making sure the large base plate see pictures 1 & 2 the top and pictures 3 & 4 the bottom
is square with each side.
If a side is off (not square) you can un-solder all but one of the tabs which lets you easily flex the material to square on the loose end and tab solder it in place. Now un-solder the last one tab and see the side easily square-up. Tab solder this end add several more tabs for a good hold.
Place the short sides in square position and tab solder them in place This is the circuit attach copper substrate for the electronic fast video amplifiers.Cover :
Solder tab the remaining cover plate and side see 3d picture
and test fit. Trim the in sides and solder tab to a snap fit.Close Edges :
Begin solder runs from tab to tab. This is IMPORTANT
, Do Not make a continuous solder run (it can buckle your box) as the solder shrinks on cooling.
Instead solder between every other or farther tabs so you have dispersed solder run sections (much like a car wheel bolt tightening sequence).
Ultimately the inside copper should be full continuous solder run.About Solder :
Hospitals, the military and I hate
lead free solder
it cracks, it ages it is Bad News. Avoid it unless you have to sell to government protected consumers.Install Battery sockets :
Layout the battery component position and mount it see picture four
. Avoid shorting the outside to inside shield by copper rim removal. I use an ohm meter to verify.
Cut and prepare a battery and regulator shield to the cover see picture three
.Input / Output :
Finally decide on your intended circuit real world connections and drill some holes for access. It is best not to short the shields with a connector body.Almost Done :
You can use a 6-32 hex-long-nut
to soldered into corners to latch the cover, see the last picture
You can place or build your electronics in the shielded copper box...